8-epi-erythromycins

ABSTRACT

1. AN ERYTHROMYCIN DERIVATIVE SELECTED FROM THE GROUP CONSISTING OF 8-EPI-10,11-ANHYDROETHYTHROMYCN B, 8-EPI11, 12-EPOXYERYTHROMYCIN A 6,9-HEMIACETAL, 8-EPI-ERYTHROMYCIN B AND 8-EPI-10,11-ANHYDROERYTHROMYCIN A.

United States Patent 3,842,068 S-EPI-ERYTHROMYCINS John Soloman Tadanier, Chicago, and Jerry Roy Martin, Waukegan, 11]., assignors to Abbott Laboratories, North Chicago, Ill. N0 Drawing. Filed June 15, 1972, Ser. No. 263,088 Int. Cl. C07c 47/18 U.S. Cl. 260210 E 4 Claims ABSTRACT OF THE DISCLOSURE Covers 8-epi-erythromycins which are useful as antibiotics.

(erythrono lide) In this formula, when R R and R represent hydrogen and R represents hydroxyl, the structure illustrated is erythromycin A. When R is, however, also hydrogen, the structure of erythromycin B is illustrated. The term erythromycin when used herein without modification is meant to embrace both forms, that is erythromycin A and erythromycin B.

Erythromycin, as will be noted from the formula, comprises three cyclic fragments. These fragments are referred to respectively as cladinose, desosamine and erythronolide. The positions on the cladinose ring are indicated by double primed numbers; the positions on the desosamine ring by single primed numbers; while positions on the erythronolide ring are indicated by unprimed numbers.

The starting materials in preparing the compounds of the invention may be 10,1l-anhydroerythromycin B, 11,12-epoxyerythromycin A, erythromycin B, or 10,11- anhydroerythromycin A. The 10,11-anhydroerythromycins A and B and 11,12-epoxyerythromycin A are best prepared as outlined in co-pending commonly assigned applications, filed as of even date, bearing Ser. Nos. 263,051 and 263,056. After providing the starting materials there are essentially three methods of epimerization.

The first method of epimerization is an acid catalyzed epimerization. A preferred acid is aqueous acetic acid. The acetic acid content may vary from about 30 to about 60% by volume. In a typical solution a 1:1 volume ratio of acetic acid to water is used here.

In a second procedure if one is starting with 10,11- anhydro derivatives, one may use a base catalyzed reaction. Greatly preferred is 1,5-diazabicyclo[5.4.0]undecene-S as a base in presence of catalytic amount of CH SO H, C H SO H, SO H,

etc. Normally this reaction is run in the presence of an inert solvent such as xylene, methylene chloride or another inert hydrocarbon, toluene or benzene for a 3,842,068 Patented Oct. 15, 1974 period of time from about 4 hours to about 50 hours and from room temperature to reflux temperature of the inert solvent.

The last mode of reaction here which is only applicable to the 11,12-epoxyerythromycin A starting material is epimerization by resort to glacial acetic acid.

The following examples illustrate preparation of the compounds of the invention.

EXAMPLE I CH3 0 Y M0113)? A crn OH 0 CH3 0on3 8-epi-10, 1 l-Anhydroerythromycin B A solution prepared from 5.3 g. of 10,11-anhydroerythromycin B, 80 ml. of glacial acetic acid, and 80 ml. of water was allowed to stand at room temperature for 49 hours. The resulting solution was added dropwise to a stirred suspension of g. of solid NaHCO in 800 ml. of water. The resulting suspension was extracted with 700 ml. of chloroform, and the chloroform solution was washed three times with 600 ml. portions of water and then dried over anhydrous magnesium sulfate. Evaporation of the chloroform solution left 5.2 g. of a white glass.

Partition column chromatography of 255 mg. of the above product gave 68 mg. of pure 8-epi-10,11-anhydroerythromycin B as a white glass, [05: 54"; k 230 nm. (510,526); IR 3610 (shoulder), 3520-3400, 1723, 1664 cmr NMR: 56.35 (C H), 3.29 (OCH3), 12.29 (NM z), 1.83 (C CH).

Analysis: Calcd. for C37H65O11N (percent): C, 63.49; H, 9.36; N, 2.00. Found (percent): C, 63.43; H, 9.56; N, 1.89.

EXAMPLE 2 8-epi-11,12-Epoxyerythromycin A 6,9-hemiacetal 3.35 (OCH 2.72 (J =10.0 Hz. C -H), 2.29 (NMe 1.58 (C -CH Analysis; Calcd. for C3qH 3011N (percent): 62.08; H, 9.15; N, 1.96. Found (percent): C, 61.95; H, 9.27; N,

4 .A, [a] -59, A 231 mm. (@8801); IR: 3604, 3550-3400, 1728, 1664 cm.- NMR: 56.45 (C -H), 3.28 (OCH 2.28 (NMe 2.08 (C CH Analysis: Calcd. for C H O N (percent): C, 62.08;

5 H, 9.15; N, 1.96. Found (percent): c, 62.15; H, 9.34;

EXAMPLE 3 N, 1.89. CH3 EXAMPLE 5 o morn) 8-epi-10,1l-Anhydroerythromycm A CH; OH HO M 10 A solution prepared from 387 mg. of 8-ep1-11,12-epoxy erythromycin A 6,9-hemiacetal, prepared by the method 0 of Example 2, 243 mg. of 1,5-diazabicyclo[5.4.0]un- O decene-S, 3.2 ml. of benzene, and 0.03 ml. of methane- 0 sulfonic acid was heated under reflux for 3 hours. The product was isolated by benzene extraction to yield 308 mg. of 8- ep i-10,1l-anhydroerythromycin A, identical with N that prepared as described in Example 4. 8 o E th 01;; OCH: EXAMPLE 6 -e 1- r rom cm Y y 8-ep1-11,12-Epoxyerythromycm A 6,9-hem1acetal A solution prepared from 1.0 g. of erythromycrn B, 17 ml. of glacial acetic acid, and 17 ml. of water was A solution prepared from 1.2 g. of 11,12-epoxyerythallowed to stand at room temperature for 96 hours. The romycin A, 20 ml. of glacial acetic acid, and 20 ml. of product was isolated as a white foam (719 mg.) by the water was allowed to stand at room temperature for 24 method described in Example 1. Partition chromatography 25 hours. The product was isolated to yield 1.1 g. of 8-epiof thls Product gave 145 of Pure -ig- 11,12-epoxyerythromycin A 6,9-hemiacetal identical with 113 IR! 3602, 35604440, 1710 that prepared by the method of Example 2. s NMRIa s); z), The compounds were then tested for their activity (C -CH 30 against gram positive and gram negative bacteria in an Analysis: Calcdfor a'z sq rz N (P agar dilution test. Results are given in agar dilution units. 9.40; Found (P 6180; These may be converted to MIC values (minimum in- N, 1.94. hibitory concentrations) expressed in micrograms/ml. by

EXAMPLE 4 merely dividing the agar dilution units into the concentration and multiplying by the proper factor. Thus, for exs)2 ample, if one tested a sample at a concentration of 4 mg./ml., and determined it had an activity of 10 agar OH dilution units, in order to determine the MIC value in micrograms/ml. one must divide the concentration of 4 by the number of agar dilution units, here 10, and multiply by 1000. O\ The compounds here were tested as to their activity CH3 against the following organisms:

" ECR =Multiple drug resistant Escherichia coli SF=Strept0c0ccus faecalis ATCC 10541 PA=Pseud0monas aeruginosa BMI-I #1, trig-10,1l-Anhydroerythmmycm A SA=Staphyloc0ccus aureus ATCC 64381" A mixture prepared from 6.0 g. of crude 10,11-anhy- E6: E h i hi li ATCC 26 droerythromycin 3.9 g. f 1,5 diaza ycl UA-m BS=Bacillus subtilis #10707 (University of Ill.) undecene-S and 0.51 ml. of methanesulfonic anhydride pvzp vulgaris ATCC 6897 was heated under reflux for 96 hours. The product, 4.8 g. S$=Shi ll Sonnet ATCC 9290- of orange glass, was isolated by benzene extraction. Parti- ST=S l ll typhosa ATCC 9992 tion column chromatography of 3.0 g. of this material KpzKlebsiella pneumoniae ATCC 10031 gave 384 mg. of pure 8-epi-10,1l-anhydroerythrornycin Results are as follows: 1

TABLE I ECRQ SF PA SA EC BS PV ss ST KP E a p g-/ 0 {11 T} 0 {328} 0 {1,338 $3 TABLE II ECR; SF PA SA EC BS PV SS ST KP E a p e L -l 0 8} 0 TABLE III ECR: SF PA SA EC BS PV SS ST KP E amp L m -l 0 $28} 0 $28} 0 233} 0 $8 TABLE IV E011 SF PA SA EC BS PV SS ST KP Mme/m1 as .j'ftfi ne); r as} 0 .23 

1. AN ERYTHROMYCIN DERIVATIVE SELECTED FROM THE GROUP CONSISTING OF 8-EPI-10,11-ANHYDROETHYTHROMYCN B, 8-EPI11, 12-EPOXYERYTHROMYCIN A 6,9-HEMIACETAL, 8-EPI-ERYTHROMYCIN B AND 8-EPI-10,11-ANHYDROERYTHROMYCIN A. 